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1.
CNS Neurosci Ther ; 30(3): e14445, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-37752787

RESUMO

INTRODUCTION: Severe spinal cord injury results in the loss of neurons in the relatively intact spinal cord below the injury area and skeletal muscle atrophy in the paralyzed limbs. These pathological processes are significant obstacles for motor function reconstruction. OBJECTIVE: We performed tail nerve electrical stimulation (TNES) to activate the motor neural circuits below the injury site of the spinal cord to elucidate the regulatory mechanisms of the excitatory afferent neurons in promoting the reconstruction of locomotor function. METHODS: Eight days after T10 spinal cord transection in rats, TNES was performed for 7 weeks. Behavioral scores were assessed weekly. Electrophysiological tests and double retrograde tracings were performed at week 8. RESULTS: After 7 weeks of TNES treatment, there was restoration in innervation, the number of stem cells, and mitochondrial metabolism in the rats' hindlimb muscles. Double retrograde tracings of the tail nerve and sciatic nerve further confirmed the presence of synaptic connections between the tail nerve and central pattern generator (CPG) neurons in the lumbar spinal cord, as well as motor neurons innervating the hindlimb muscles. CONCLUSION: The mechanisms of TNES induced by the stimulation of primary afferent nerve fibers involves efficient activation of the motor neural circuits in the lumbosacral segment, alterations of synaptic plasticity, and the improvement of muscle and nerve regeneration, which provides the structural and functional foundation for the future use of cutting-edge biological treatment strategies to restore voluntary movement of paralyzed hindlimbs.


Assuntos
Traumatismos da Medula Espinal , Cauda , Ratos , Animais , Cauda/inervação , Cauda/metabolismo , Cauda/patologia , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/terapia , Traumatismos da Medula Espinal/patologia , Medula Espinal/patologia , Neurônios Motores/patologia , Músculo Esquelético/patologia , Estimulação Elétrica , Atrofia/patologia
2.
Sci Rep ; 13(1): 12470, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37528124

RESUMO

Disulfidptosis is a newly discovered form of cell death. Not yet clearly classified as programmed cell death or accidental cell death. This study aimed to create a novel disulfidptosis-related lncRNA index (DLI) that can be used to predict survival and chemotherapy drugs sensitivity in patients with cervical cancer. First of all, we found lncRNAs associated with disulfidptosis between cervical cancer tissues and normal tissues. By LASSO-Cox analysis, overlapping lncRNAs were then used to construct lncRNA index associated with disulfidptosis, which can be served to predict the prognosis of patients with CC, especially the chemotherapy drugs sensitivity. ROC curves and PCA based on DLI and clinical signatures were developed and demonstrated to have good predictive potential. In addition, differences in immune cell subset infiltration and differences in immune checkpoint expression between high-DLI and low-DLI groups were analyzed, and we investigated the relationship between the DLI and tumor mutation burden (TMB). In summary, we constructed a lncRNA prediction index associated with disulfidptosis. This has important clinical implications, including improving the predictive value of cervical cancer patients and providing a biomarker for cervical cancer guiding individualized treatment.


Assuntos
RNA Longo não Codificante , Neoplasias do Colo do Útero , Humanos , Feminino , RNA Longo não Codificante/genética , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/genética , Prognóstico , Apoptose , Morte Celular
3.
Biomaterials ; 297: 122103, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37028111

RESUMO

Following transected spinal cord injury (SCI), there is a critical need to restore nerve conduction at the injury site and activate the silent neural circuits caudal to the injury to promote the recovery of voluntary movement. In this study, we generated a rat model of SCI, constructed neural stem cell (NSC)-derived spinal cord-like tissue (SCLT), and evaluated its ability to replace injured spinal cord and repair nerve conduction in the spinal cord as a neuronal relay. The lumbosacral spinal cord was further activated with tail nerve electrical stimulation (TNES) as a synergistic electrical stimulation to better receive the neural information transmitted by the SCLT. Next, we investigated the neuromodulatory mechanism underlying the action of TNES and its synergism with SCLT in SCI repair. TNES promoted the regeneration and remyelination of axons and increased the proportion of glutamatergic neurons in SCLT to transmit brain-derived neural information more efficiently to the caudal spinal cord. TNES also increased the innervation of motor neurons to hindlimb muscle and improved the microenvironment of muscle tissue, resulting in effective prevention of hindlimb muscle atrophy and enhanced muscle mitochondrial energy metabolism. Tracing of the neural circuits of the sciatic nerve and tail nerve identified the mechanisms responsible for the synergistic effects of SCLT transplantation and TNES in activating central pattern generator (CPG) neural circuits and promoting voluntary motor function recovery in rats. The combination of SCLT and TNES is expected to provide a new breakthrough for patients with SCI to restore voluntary movement and control their muscles.


Assuntos
Traumatismos da Medula Espinal , Regeneração da Medula Espinal , Ratos , Animais , Cauda , Regeneração Nervosa/fisiologia , Medula Espinal , Traumatismos da Medula Espinal/terapia , Axônios/fisiologia , Neurônios Motores/fisiologia , Estimulação Elétrica , Recuperação de Função Fisiológica/fisiologia
4.
Foods ; 12(6)2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36981105

RESUMO

The "Dangshan" pear woolliness response is a physiological disease that causes large losses for fruit farmers and nutrient inadequacies.The cause of this disease is predominantly a shortage of boron and calcium in the pear and water loss from the pear. This paper used the fusion of near-infrared Spectroscopy (NIRS) and Computer Vision Technology (CVS) to detect the woolliness response disease of "Dangshan" pears. This paper employs the merging of NIRS features and image features for the detection of "Dangshan" pear woolliness response disease. Near-infrared Spectroscopy (NIRS) reflects information on organic matter containing hydrogen groups and other components in various biochemical structures in the sample under test, and Computer Vision Technology (CVS) captures image information on the disease. This study compares the results of different fusion models. Compared with other strategies, the fusion model combining spectral features and image features had better performance. These fusion models have better model effects than single-feature models, and the effects of these models may vary according to different image depth features selected for fusion modeling. Therefore, the model results of fusion modeling using different image depth features are further compared. The results show that the deeper the depth model in this study, the better the fusion modeling effect of the extracted image features and spectral features. The combination of the MLP classification model and the Xception convolutional neural classification network fused with the NIR spectral features and image features extracted, respectively, was the best combination, with accuracy (0.972), precision (0.974), recall (0.972), and F1 (0.972) of this model being the highest compared to the other models. This article illustrates that the accuracy of the "Dangshan" pear woolliness response disease may be considerably enhanced using the fusion of near-infrared spectra and image-based neural network features. It also provides a theoretical basis for the nondestructive detection of several techniques of spectra and pictures.

5.
Cartilage ; 14(2): 144-151, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36541677

RESUMO

OBJECTIVE: The current study aims to investigate the factors that could predict response to intra-articular corticosteroid injection (IACI) in patients with knee osteoarthritis (KOA). METHODS: Data of participants were retrieved from the Osteoarthritis Initiative database. Participants with at least one IACI treatment on single or bilateral knees within the first 5 years of follow-up were retrospectively included. Demographic data, clinical and radiographic variables were collected at both baseline and the first follow-up after IACI treatment. Positive response to IACI treatment was defined as >20% reduction of Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain score from V0 to V1. All the variables with P < 0.2 after the comparison between the response and non-response groups were included in a multivariable logistic regression model to identify independent response predictive patient-specific valuables. Receiver operating characteristic curves were performed to establish the cutoff values of independent predictors. RESULTS: The current study included a total of 385 participants (473 knees), with 155 and 318 knees classified into the response group and non-response group, respectively. Those with satisfied responses to IACI treatment had significantly higher WOMAC pain score (P < 0.001), disability score (P = 0.002), and stiffness score (P = 0.015) at the baseline. Baseline WOMAC pain score showed significant association with positive response to IACI treatment in multivariate logistic analysis and the best cutoff value was 5 points. The rate of analgesics utilization was lower (P = 0.014) in the response group than the non-response group after the IACI treatment. CONCLUSION: KOA patients with a baseline WOMAC pain score ≥5 are more likely to benefit from IACI treatment.


Assuntos
Osteoartrite do Joelho , Humanos , Osteoartrite do Joelho/complicações , Osteoartrite do Joelho/tratamento farmacológico , Estudos Retrospectivos , Resultado do Tratamento , Dor/tratamento farmacológico , Esteroides
6.
Front Neurol ; 13: 999375, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36119697

RESUMO

Objectives: Spinal cord injury (SCI) remodels the brain structure and alters brain function. To identify specific changes in brain gray matter volume (GMV) and white matter volume (WMV) following SCI, we conducted a voxel-based meta-analysis of whole-brain voxel-based morphometry (VBM) studies. Methods: We performed a comprehensive literature search on VBM studies that compared SCI patients and healthy controls in PubMed, Web of Science and the China National Knowledge Infrastructure from 1980 to April 2022. Then, we conducted a voxel-based meta-analysis using seed-based d mapping with permutation of subject images (SDM-PSI). Meta-regression analysis was performed to identify the effects of clinical characteristics. Results: Our study collected 20 studies with 22 GMV datasets and 15 WMV datasets, including 410 patients and 406 healthy controls. Compared with healthy controls, SCI patients showed significant GMV loss in the left insula and bilateral thalamus and significant WMV loss in the bilateral corticospinal tract (CST). Additionally, a higher motor score and pinprick score were positively related to greater GMV in the right postcentral gyrus, whereas a positive relationship was observed between the light touch score and the bilateral postcentral gyrus. Conclusion: Atrophy in the thalamus and bilateral CST suggest that SCI may trigger neurodegeneration changes in the sensory and motor pathways. Furthermore, atrophy of the left insula may indicate depression and neuropathic pain in SCI patients. These indicators of structural abnormalities could serve as neuroimaging biomarkers for evaluating the prognosis and treatment effect, as well as for monitoring disease progression. The application of neuroimaging biomarkers in the brain for SCI may also lead to personalized treatment strategies. Systematic review registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021279716, identifier: CRD42021279716.

7.
Sensors (Basel) ; 22(14)2022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-35890889

RESUMO

Accurate lane detection is an essential function of dynamic traffic perception. Though deep learning (DL) based methods have been widely applied to lane detection tasks, such models rarely achieve sufficient accuracy in low-light weather conditions. To improve the model accuracy in foggy conditions, a new approach was proposed based on monocular depth prediction and an atmospheric scattering model to generate fog artificially. We applied our method to the existing CULane dataset collected in clear weather and generated 107,451 labeled foggy lane images under three different fog densities. The original and generated datasets were then used to train state-of-the-art (SOTA) lane detection networks. The experiments demonstrate that the synthetic dataset can significantly increase the lane detection accuracy of DL-based models in both artificially generated foggy lane images and real foggy scenes. Specifically, the lane detection model performance (F1-measure) was increased from 11.09 to 70.41 under the heaviest foggy conditions. Additionally, this data augmentation method was further applied to another dataset, VIL-100, to test the adaptability of this approach. Similarly, it was found that even when the camera position or level of brightness was changed from one dataset to another, the foggy data augmentation approach is still valid to improve model performance under foggy conditions without degrading accuracy on other weather conditions. Finally, this approach also sheds light on practical applications for other complex scenes such as nighttime and rainy days.


Assuntos
Condução de Veículo , Acidentes de Trânsito , Algoritmos , Coleta de Dados , Tempo (Meteorologia)
8.
J Orthop Translat ; 36: 8-17, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35891923

RESUMO

Background: Degenerative diseases in orthopaedics have become a significant global public health issue with the aging of the population worldwide. The traditional medical interventions, including physical therapy, pharmacological therapy and even surgery, hardly work to modify degenerative progression. Stem cell-based therapy is widely accepted to treat degenerative orthopaedic disease effectively but possesses several limitations, such as the need for strict monitoring of production and storage and the potential risks of tumorigenicity and immune rejection in clinical translation. Furthermore, the ethical issues surrounding the acquisition of embryonic stem cells are also broadly concerned. Exosome-based therapy has rapidly grown in popularity in recent years and is regarded as an ideal alternative to stem cell-based therapy, offering a promise to achieve 'cell-free' tissue regeneration. Methods: Traditionally, the native exosomes extracted from stem cells are directly injected into the injured site to promote tissue regeneration. Recently, several modified exosome-based strategies were developed to overcome the limitations of native exosomes, which include mainly exogenous molecule loading and exosome delivery through scaffolds. In this paper, a systematic review of the exosome-based strategy for degenerative disease in orthopaedics is presented. Results: Treatment strategies based on the native exosomes are effective but with several disadvantages such as rapid diffusion and insufficient and fluctuating functional contents. The modified exosome-based strategies can better match the requirements of the regeneration in some complex healing processes. Conclusion: Exosome-based strategies hold promise to manage degenerative disease in orthopaedics prior to patients reaching the advanced stage of disease in the future. The timely summary and highlights offered herein could provide a research perspective to promote the development of exosome-based therapy, facilitating the clinical translation of exosomes in orthopaedics. Translational potential of this article: Exosome-based therapy is superior in anti-senescence and anti-inflammatory effects and possesses lower risks of tumorigenicity and immune rejection relative to stem cell-based therapy. Exosome-based therapy is regarded as an ideal alternative to stem cell-based therapy, offering a promise to achieve 'cell-free' tissue regeneration.

10.
Front Pharmacol ; 12: 778041, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34776987

RESUMO

Traditional Chinese medicine (TCM) has demonstrated superior therapeutic effect for musculoskeletal diseases for thousands of years. Recently, the herbal extracts of TCM have received rapid advances in musculoskeletal tissue engineering (MTE). A literature review collecting both English and Chinese references on bioactive herbal extracts of TCM in biomaterial-based approaches was performed. This review provides an up-to-date overview of application of TCMs in the field of MTE, involving regulation of multiple signaling pathways in osteogenesis, angiogenesis, anti-inflammation, and chondrogenesis. Meanwhile, we highlight the potential advantages of TCM, opening the possibility of its extensive application in MTE. Overall, the superiority of traditional Chinese medicine turns it into an attractive candidate for coupling with advanced additive manufacturing technology.

11.
Mater Today Bio ; 12: 100141, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34632364

RESUMO

Autogenous healing of osteoporotic fractures is challenging, as the regenerative capacity of bone tissues is impaired by estrogen reduction and existed pro-inflammatory cytokines. In this study, a biofunctional ginsenoside Rg1 and strontium-containing mineral (SrHPO4, SrP)-incorporated biodegradable silk fibroin-gelatin (SG) scaffold (Rg1/SrP/SG) was developed to stimulate the osteoporotic bone repair. The incorporation of 15 wt% SrP significantly enhanced the mechanical strength, stimulated the osteogenic differentiation of mouse bone marrow mesenchymal stem cells, and suppressed the osteoclastogenesis of RAW264.7 in a concentration-related manner. The loading of Rg1 in SG and 15SrP/SG scaffolds obviously promoted the angiogenesis of human umbilical vein endothelial cells via activating the expression of vascular endothelial growth factor and basic fibroblast growth factor genes and proteins. The bioactive strontium ions (Sr2+) and Rg1 released from the scaffolds together mediated lipopolysaccharide-treated macrophages polarizing into M2 type. They downregulated the expression of inflammatory-related genes (interleukin (IL)-1ß, tumor necrosis factor α, and IL-6) and stimulated the expression of genes related to anti-inflammation (Arginase and IL-10) as well as bone repair (BMP-2 and PDGF-BB) in the macrophages. The in vivo results also displayed that SrP and Rg1 significantly promoted the bone repair effect of SG scaffolds in osteoporotic critical-sized calvarial defects. Besides, the degradation rate of the scaffolds was close to the bone regeneration rate. Therefore, the simultaneous addition of SrP and Rg1 is a promising way for facilitating the osteoporotic bone repair activity of SG scaffolds via promoting the osteogenesis and angiogenesis, as well as inhibiting the osteoclastogenesis and inflammation.

12.
Ann Transl Med ; 9(9): 768, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34268381

RESUMO

BACKGROUND: The purpose of this study was to develop an optimal diabetes-osteoarthritis (DM-OA) mouse model to validate that diabetes aggravates osteoarthritis (OA) and to evaluate the microarchitecture, chemical composition, and biomechanical properties of subchondral bone (SB) as a consequence of the DM-OA-induced damage induced. METHODS: Mice were randomly divided into three groups: DM-OA group, OA group, and sham group. Blood glucose levels, body weight, and food intake of all animals were recorded. Serum calcium (Ca) and osteocalcin (OCN) levels were compared in the three groups. The messenger ribonucleic acid (mRNA) and protein expression of key regulators for bone metabolism were detected. A semi-quantitative grading system [Osteoarthritis Research Society International (OARSI)] was used to evaluate cartilage and SB degeneration. Microspectroscopy, microindentations, micro-computed tomography (CT) imaging, and fracture load of compression testing were also used to evaluate trabecular SB properties. RESULTS: Glycemic monitoring and pancreas pathological results indicated stable high blood glucose and massive destruction of pancreas and islet cells in the DM-OA group. Serum levels of bone specific alkaline phosphatase (ALP-B) and tartrate-resistant acid phosphatase 5b (TRACP-5b) in the DM-group were higher than those of the other two groups while levels of serum Ca and OCN were lower. Meanwhile, the protein and mRNA expression of osteoblast-specific biomarkers [osteoprotegerin/receptor activator of nuclear factor kappa-B ligand (OPG/RANKL) ratio, collagen type I (COL-I), Runt-related transcription factor 2 (RUNX-2), OCN] were suppressed, and osteoclast-specific biomarkers [sclerostin (SOST)] was elevated in the DM-OA group. The mineral-to-collagen ratio, microindentation elastic modulus, hardness, micro-architectural parameters, bone mineral density, and fracture load of SB trabecular bone of the DM-OA group joint were lower than those of the other two groups. On the other hand, The OARSI score, trabecular spacing, and structural model index of the DM-OA group joint were higher than those of the other two groups. CONCLUSIONS: The glycemic and pancreatic pathological results indicated that the DM-OA model was a simple and reliable model induced by streptozotocin (STZ) and surgery. The results revealed the mechanisms through which diabetes accelerates OA; that is, by damaging and deteriorating the functions of SB, including its microarchitecture, chemical composition, and biomechanical properties.

13.
Biomaterials ; 274: 120865, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33991950

RESUMO

Osteoarthritis (OA) is one of the most common joint diseases worldwide and the focus is shifting to disease prevention and the pharmaceutical and surgical treatment of early OA. However, at present few have proven ability to block or delay the progression of OA. Nevertheless, M2 macrophages present an anti-inflammatory function and promote cartilage repair, thereby alleviating OA in mice. However, it is a significant challenge to regulate the helpful secretion of M2 macrophages on demand toward disease-modifying osteoarthritis therapeutics. Here, artificial M2 macrophage (AM2M) with yolk-shell structure was proposed and fabricated to enhance the therapeutic efficacy of M2 macrophages in the treatment of OA. AM2M was composed of macrophage membrane as "shell" and inflammation-responsive nanogel as "yolk". The nanogel was prepared via physical interaction of gelatin and chondroitin sulfate (ChS) through ionic bond and hydrogen bond, achieving burst release to down-regulate inflammation during acute flares and sustainable release to repair cartilage during low inflammatory activity. Furthermore, AM2M exhibited the targeting and long-term residence in the inflamed area and blocked the immune stimulation of macrophages by ChS. Therefore, our fabrication provided a new insight that artificial M2 macrophages are expected to break a vicious and self-perpetuating cycle of OA.


Assuntos
Osteoartrite , Animais , Inflamação , Macrófagos , Camundongos , Osteoartrite/tratamento farmacológico
14.
Transfus Apher Sci ; 60(3): 103079, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33602623

RESUMO

Whether platelet (PLT) microRNA (miRNA) profiles are affected by pathogen reduction technology (PRT) using vitamin B2 and ultraviolet-B (VB2-PRT) remains unclear. Samples from VB2-PRT-treated (experimental group, E_) and untreated (control group, C_) apheresis PLTs were taken on days 1, 3 and 5 of storage, designated as E_1, E_3, E_5, C_1, C_3 and C_5, respectively. The miRNA expression profiles were assessed by DNA Nano Ball (DNB) sequencing technology, and verified by quantitive real-time fluorescence quantitative PCR (qRT-PCR). Compared with the expression profiles of PLT miRNAs, 3895 miRNAs were identified in the E_ groups while 4106 were in the C_ groups. There were 487 significant differentially expressed miRNAs in E_1 vs C_1 group, including 220 upregulated and 287 downregulated, such as miR-146a-5p and let-7b-5p. There were 908 significant differentially expressed miRNAs in E_3 vs C_3 group, including 297 upregulated and 611 downregulated, such as miR-142-5p and miR-7-5p. There were 229 significant differentially expressed miRNAs in E_5 vs C_5 group, including 80 upregulated and 149 downregulated, such as miR-3529-3p and miR-451a. These differentially expressed miRNAs had been suggested to have functional roles in energy homeostasis, cell communication, proliferation, migration and apoptosis. GO analysis showed a significant enrichmen in relevant biological process categories as receptor activity, signal transduction, cell transport, motility and chemotaxis. The significantly enriched KEGG pathway of predicted target genes was Glycosaminoglycan biosynthesis in E_ vs C_ groups. These new observation could provide insights on the understanding of change of miRNA profiles of PLT treated with VB2-PRT.


Assuntos
Coleta de Amostras Sanguíneas/métodos , Perfilação da Expressão Gênica/métodos , MicroRNAs/metabolismo , Plaquetoferese/métodos , Riboflavina/uso terapêutico , Humanos , Riboflavina/farmacologia
15.
ACS Appl Bio Mater ; 4(9): 6630-6646, 2021 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-35006966

RESUMO

Musculoskeletal engineering has been considered as a promising approach to customize regenerated tissue (such as bone, cartilage, tendon, and ligament) via a self-healing performance. Recent advances have demonstrated the great potential of bioactive materials for regenerative medicine. Silk fibroin (SF), a natural polymer, is regarded as a remarkable bioactive material for musculoskeletal engineering thanks to its biocompatibility, biodegradability, and tunability. To improve tissue-engineering performance, silk fibroin is hybridized with other biomaterials to form silk-fibroin-based hybrid biomaterials, which achieve superior mechanical and biological performance. Herein, we summarize the recent development of silk-based hybrid biomaterials in musculoskeletal tissue with reasonable generalization and classification, mainly including silk fibroin-based inorganic and organic hybrid biomaterials. The applied inorganics are composed of calcium phosphate, graphene oxide, titanium dioxide, silica, and bioactive glass, while the polymers include polycaprolactone, collagen (or gelatin), chitosan, cellulose, and alginate. This article mainly focuses on the physical and biological performances both in vitro and in vivo study of several common silk-based hybrid biomaterials in musculoskeletal engineering. The timely summary and highlight of silk-fibroin-based hybrid biomaterials will provide a research perspective to promote the further improvement and development of silk fibroin hybrid biomaterials for improved musculoskeletal engineering.


Assuntos
Fibroínas , Materiais Biocompatíveis/uso terapêutico , Osso e Ossos/cirurgia , Fibroínas/uso terapêutico , Polímeros , Seda , Alicerces Teciduais
16.
Front Oncol ; 10: 578985, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33224880

RESUMO

PURPOSE: In this study, we aimed to use 3T magnetic resonance imaging (MRI), which is clinically available, to determine the extracellular pH (pHe) of liver tumors and prospectively evaluate the ability of chemical exchange saturation transfer (CEST) MRI to distinguish between benign and malignant liver tumors. METHODS: Different radiofrequency irradiation schemes were assessed for ioversol-based pH measurements at 3T. CEST effects were quantified in vitro using the asymmetric magnetization transfer ratio (MTRasym) at 4.3 ppm from the corrected Z spectrum. Generalized ratiometric analysis was conducted by rationing resolved ioversol CEST effects at 4.3 ppm at a flip angle of 60 and 350°. Fifteen patients recently diagnosed with hepatic carcinoma and five patients diagnosed with hepatic hemangioma [1 male; mean age, 48.6 (range, 37-59) years] were assessed. RESULTS: By conducting dual-power CEST MRI, the pH of solutions was determined to be 6.0-7.2 at 3T in vitro. In vivo, ioversol signal intensities in the tumor region showed that the extracellular pH in hepatic carcinoma was acidic(mean ± standard deviation, 6.66 ± 0.19), whereas the extracellular pH was more physiologically neutral in hemangioma (mean ± standard deviation, 7.34 ± 0.09).The lesion size was similar between CEST pH MRI and T2-weighted imaging. CONCLUSION: dual-power CEST MRI can detect extracellular pH in human liver tumors and can provide molecular-level diagnostic tools for differentiating benign and malignant liver tumors at 3T.

17.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 37(9): 987-990, 2020 Sep 10.
Artigo em Chinês | MEDLINE | ID: mdl-32820513

RESUMO

OBJECTIVE: To analyze the action of miRNA-326 on its target gene BCL-XL and the molecular mechanism of platelet apoptosis regulated by miRNAs. METHODS: Dual-luciferase vectors containing respectively the wild-type and mutant 3'-untranslated region (3'UTR) fragments of the BCL-XL gene were constructed with firefly and renilla luciferases and transfected into 293T cells. Relative fluorescence intensities of the transfected cells were measured. RESULTS: Dual-luciferase reporter gene vectors for PsiCHECK- BCL-XL -3'UTR-WT (wild-type) and PsiCHECK- BCL-XL -3' UTR-MT (variant) were respectively constructed. Relative fluorescence intensities of the 293T cells co-transfected by miRNA-326 and PsiCHECK- BCL-XL -3'UTR-WT plasmid were significantly lower compared with the control group (co-transfected by a miRNA-326 negative sequence and PsiCHECK- BCL-XL -3' UTR-WT plasmid) ( P = 0.034). The relative fluorescence intensity was also significantly reduced in cells co-transfected by miRNA-326 and PsiCHECK- BCL-XL -3' UTR-WT plasmid compared with the mutant control group co-transfected by miRNA-326 and PsiCHECK- BCL-XL -3'UTR-MT plasmid (P = 0.022). CONCLUSION: miRNA-326 may participate in the regulation of platelet apoptosis by acting on the 3'-UTR of the BCL-XL gene.


Assuntos
Regiões 3' não Traduzidas , Apoptose , Plaquetas/citologia , MicroRNAs/genética , Proteína bcl-X/genética , Genes Reporter , Células HEK293 , Humanos , Luciferases/genética
18.
ACS Chem Neurosci ; 11(13): 1978-1984, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32492333

RESUMO

Dysfunction of the glymphatic system may play a significant role in the development of neurodegenerative diseases. However, in vivo imaging of the glymphatic system is challenging. In this study, we describe an unconventional MRI method for imaging the glymphatic system based on chemical exchange saturation transfer, which we tested in an in vivo porcine model of impaired glymphatic function. The blood, lymph, and cerebrospinal fluid (CSF) from one pig were used for testing the MRI effect in vitro at 7 Tesla (T). Unilateral deep cervical lymph node ligation models were then performed in 20 adult male Sprague-Dawley rats. The brains were scanned in vivo dynamically after surgery using the new MRI method. Behavioral tests were performed after each scanning session and the results were tested for correlations with the MRI signal intensity. Finally, the pathological assessment was conducted in the same brain slices. The special MRI effect in the lymph was evident at about 1.0 ppm in water and was distinguishable from those of blood and CSF. In the model group, the intensity of this MRI signal was significantly higher in the ipsilateral than in the contralateral hippocampus. The correlation between the signal abnormality and the behavioral score was significant (Pearson's, R2 = 0.9154, p < 0.005). We conclude that the novel MRI method can visualize the glymphatic system in vivo.


Assuntos
Sistema Glinfático , Animais , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Ratos , Ratos Sprague-Dawley , Suínos
19.
J Orthop Translat ; 22: 67-72, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32440501

RESUMO

OBJECTIVES: The objective of this study was to investigate the effect of botulinum toxin type A (BTX-A)-induced quadriceps muscle atrophy on the cartilage and subchondral bone in an otherwise intact rat joint model. METHODS: The rat right quadriceps muscle atrophy was established by intramuscular injection of BTX-A. Twenty-four rats were divided randomly into 3 groups: The BTX-A-treated 4-week group; the BTX-A-treated 8-week group; and the control group injected with phosphate buffer saline were observed for 8 weeks. Muscle atrophy level was measured by weighing and histology examinations. Serum interleukin-1ß level was tested by ELISA (enzyme linked immunosorbent assay); the subchondral bone was analysed by micro-computed tomography and the cartilage was measured by histology examinations (gross view, haematoxylin and eosin staining and Safranin-O/fast green staining) and immunohistochemistry test {collagen X [ColX]}. RESULTS: BTX-A intramuscular injection led to muscle atrophy. Characteristics of muscle atrophy appeared in two BTX-A-injected groups but not in the control group. Quadriceps atrophy did not affect interleukin-1ß level in serum, but resulted in subchondral bone abnormal changes with reduced bone volume/total tissue volume â€‹and increased Structure Model Index. Furthermore, the more the severe cartilage damage, the higher the histologic damage scores, followed by the higher the percentage of collagen X-positive chondrocytes caused by muscle atrophy. CONCLUSIONS: Quadriceps muscle atrophy triggered the subchondral bone abnormal change and cartilage degeneration, which would be a risk factor for development of osteoarthritis. THE TRANSLATIONAL POTENTIAL OF THIS ARTICLE: Our results indicate that anti-quadriceps muscle atrophy can be a candidate therapeutic target in the prevention of knee osteoarthritis.

20.
Front Chem ; 8: 326, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32391334

RESUMO

Theranostic agents are particles containing both diagnostic and medicinal agents in a single platform. Theranostic approaches often employ nanomedicine because loading both imaging probes and medicinal drugs onto nanomedicine particles is relatively straightforward, which can simultaneously provide diagnostic and medicinal capabilities within a single agent. Such systems have recently been described as nanotheranostic. Currently, nanotheranostic particles incorporating medicinal drugs are being widely explored with multiple imaging methods, including computed tomography, positron emission tomography, single-photon emission computed tomography, magnetic resonance imaging, and fluorescence imaging. However, most of these particles are metal-based multifunctional nanotheranostic agents, which pose potential toxicity or radiation risks. Hence, alternative non-metallic and biocompatible nanotheranostic agents are urgently needed. Recently, nanotheranostic agents that combine medicinal drugs and chemical exchange saturated transfer (CEST) contrast agents have shown good promise because CEST imaging technology can utilize the frequency-selective radiofrequency pulse from exchangeable protons to indirectly image without requiring metals or radioactive agents. In this review, we mainly describe the fundamental principles of CEST imaging, features of nanomedicine particles, potential applications of nanotheranostic agents, and the opportunities and challenges associated with clinical transformations.

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